Provided is a flexo printing plate which makes it possible to perform printing in which the discontinuity of density is not visually recognized by inhibiting the enlargement of halftone dots in the boundary between an image portion having a low halftone dot area ratio and a non-image portion. The flexo printing plate adopts a constitution in which, within the highlight halftone dot portion having a halftone dot area ratio of higher than 0% and equal to or lower than 10%, among the small dots constituting the highlight halftone dot portion, at least one small dot adjacent to the non-image portion that continues 10 mm or further in a direction separating from the edge of the highlight halftone dot portion has a height smaller than the average height of the small dots of the highlight halftone dot portion.

The present invention relates to a method for producing three-dimensional macroscopic patterns in liquid-crystalline coatings, patterned layers containing liquid-crystalline materials and produced by said method, and the use thereof in decorative and security products. In the method, the liquid-crystalline coating in a non-solidified state is brought into contact with a printing form for a relief printing method, with the result that depressions which are not deeper than 10 μm arise in the coating.

A method of adjusting the print repeat length of a print image in a multicolor rotary printing machine, particularly a flexographic printing press, having a central impression cylinder, a first plate cylinder, and a second plate cylinder, including modifying the peripheral velocity of the first plate cylinder and the peripheral velocity of the second plate cylinder during printing operation, relative to the peripheral velocity of the central impression cylinder, and adjusting the longitudinal register of the first plate cylinder having the modified peripheral velocity and the longitudinal register of the second plate cylinder having the modified peripheral velocity.

A method of adjusting the print repeat length of a print image in a multicolor rotary printing machine, particularly a flexographic printing press, having a central impression cylinder, a first plate cylinder, and a second plate cylinder, including modifying the peripheral velocity of the first plate cylinder and the peripheral velocity of the second plate cylinder during printing operation, relative to the peripheral velocity of the central impression cylinder, and adjusting the longitudinal register of the first plate cylinder having the modified peripheral velocity and the longitudinal register of the second plate cylinder having the modified peripheral velocity.

A flexographic printer is provided with: a printing plate for transferring ink at an ink transfer site to an object to be printed S; an anilox roll for supplying ink to the printing plate at an ink supply site; a plate cylinder on which the printing plate is wound and rotated; and an ink solvent supply unit for supplying a solvent for the ink on the surface of the printing plate in a post-ink transfer region that is downstream of the ink transfer site in the plate cylinder rotation direction and upstream of the ink supply site in the plate cylinder rotation direction.

A flexographic printer is provided with: a printing plate for transferring ink at an ink transfer site to an object to be printed S; an anilox roll for supplying ink to the printing plate at an ink supply site; a plate cylinder on which the printing plate is wound and rotated; and an ink solvent supply unit for supplying a solvent for the ink on the surface of the printing plate in a post-ink transfer region that is downstream of the ink transfer site in the plate cylinder rotation direction and upstream of the ink supply site in the plate cylinder rotation direction.

A mandrel for use in a printing apparatus includes a substantially cylindrical mandrel shaft and plastic expansion rings that are slidably and coaxially mounted on the mandrel shaft. The mandrel also includes a locking assembly including a fixed stop ring and a single locking ring that is axially movably mounted on the mandrel shaft. The expansion rings are positioned between the stop ring and the locking ring. In the unlocked position of the locking ring the expansion rings are in a released state in which the axial compression and the radial expansion of the expansion rings are smaller than in a locked position of the locking ring. A printing cylinder sleeve can be fixedly connected to the mandrel by bringing the expansion rings in the radially expanded state. When the printing cylinder sleeve has to be exchanged, this is feasible when the expansion rings are in the released state.

The invention relates to a printing sleeve (1) comprising a first, radially inner layer (11) that has an inner side (11a) for making direct contact with the outer side of a printing cylinder (10), and an outer side (11b) which lies radially opposite said inner side (11a); as well as a second, radially outer layer (12) that has an outer side (12b) for forming a printing surface, and an inner side (12a) which lies radially opposite said outer side (12b). Said printing sleeve (1) is characterised in that the outer side (11b) of the first, radially inner layer (11) and the inner side (12a) of the second, radially outer layer (12) lie directly one against the other, and in that said first, radially inner layer (11) is designed to be able to absorb both forces occurring in the circumferential direction (U) and/or longitudinal direction (L), and pressures that arise in the radial direction (R).

The invention relates to a printing sleeve (1) comprising a first, radially inner layer (11) that has an inner side (11a) for making direct contact with the outer side of a printing cylinder (10), and an outer side (11b) which lies radially opposite said inner side (11a); as well as a second, radially outer layer (12) that has an outer side (12b) for forming a printing surface, and an inner side (12a) which lies radially opposite said outer side (12b). Said printing sleeve (1) is characterised in that the outer side (11b) of the first, radially inner layer (11) and the inner side (12a) of the second, radially outer layer (12) lie directly one against the other, and in that said first, radially inner layer (11) is designed to be able to absorb both forces occurring in the circumferential direction (U) and/or longitudinal direction (L), and pressures that arise in the radial direction (R).

According to aspects of the embodiments, there is provided methods to measure characteristics of line width and density of printed test patterns. By printing the test patterns and capturing with an in-line scanner or optical device, the analytical results of these test patterns can be used as feedback to a control system that adjusts both impression and inking levels without the need of a skilled operator.